How much does a royal wedding cost?

The guest list and the exact date have not been revealed, but one thing is certain: Prince Harry and Meghan Markle's wedding will be expensive.

Aimee Dunne, a London-based wedding planner who specializes in luxury weddings, said that even conservative estimates for a modern royal wedding would start well into six figures.

"I can't imagine Harry and Meghan would be able to achieve the wedding they would be looking at on anything less than £500,000 + ($670,000)," she said.

Kensington Palace confirmed on Tuesday that the wedding will take place at St. George's Chapel in Windsor Castle. Dunne said that choosing a venue outside central London will help keep spending down.

But the total cost could skyrocket into the millions when security is included.

"Security at such a historic building would also no doubt be a big consideration, especially with recent security threats and terrorist concerns," said Dunne.

Here's a look at the money behind a royal wedding:

Who pays?

Kensington Palace said Tuesday that the royal family will pay for the May 2018 wedding, despite the bill traditionally being footed by the bride's family.

Sarah Haywood, a wedding planner in London, said the fact that the royal family will pay for the wedding indicates it will not be an official State occasion.

"The celebration will not need to include the number of international royals and foreign and domestic dignitaries that protocol dictated for Prince William's wedding as a future King of England," said Haywood.

"Therefore Windsor is ideal and a more intimate choice," she added.

The reception

Harry's brother, William and his wife, Catherine, had two receptions in Buckingham Palace: a traditional lunch for over 600 guests, which was hosted by the Queen and included dignitaries and officials.

A more intimate evening party for roughly 300 friends and family followed.